I can't relate to you, since I have a very different personality on how I present my art, but I can understand.
DA is a good place to show art, like you have been doing, and also what Twin said is absolutely true, loads of people just manipulate art with Photoshop and claim it as their own, so it gets a bad name.
High ego is where you're going wrong, I find it's best to be modest with anything. I'm apparently talented with art, but I never show off or act really good about it. I point out all the flaws myself to others to demonstrate that I have a willingness to improve and show that I know I'm not the best.
Being proud of your art work is good, a happy display you give out from your pleasure with art is always good. But taking it too far annoys people, and having massive egos always turns people off and that causes nasty remarks like you experienced.
When you put your art online, you're asking for any opinions, fantastic or horrible. You're not always going to get the ones you want, I myself usually get people loving my work, so that's why I made a thread earlier in the year asking for everyone to absolutely bash it and nitpick everything they found wrong. I didn't take that badly either, I wanted to improve, and negatives comments is the best way for me to do that.
So I suggest, just either tone down your ego a little, or not give a crap about people say.